var WriteHTTP;
var ReadXML;
var WriteReadXML;
var MAX = 0;
var NAME = "";

function LOGGER(TEXT)
{
/*
	var now = new Date();
	var timeNow = now.getHours()+":"+now.getMinutes()+":"+now.getSeconds();
	var DEBUG = document.getElementById("DEBUG");
	var div = document.createElement('div');
	div.innerHTML = timeNow+" : "+TEXT;
	DEBUG.insertBefore(div, DEBUG.firstChild);
*/
}


function GetXmlHttpObject()
{
	var obj=null;
	try
	{
	 	// Firefox, Opera 8.0+, Safari
		obj=new XMLHttpRequest();
	}
	catch (e)
	{
	 	// Internet Explorer
	 	try
	  	{
	  		obj=new ActiveXObject("Msxml2.XMLHTTP");
		}
	 	catch (e)
	  	{
			obj=new ActiveXObject("Microsoft.XMLHTTP");
		}
	}
	return obj;
}

function MessageKeyHandler(e) 
{
	var MESSAGE = document.getElementById("MESSAGE");
	var NAME = document.getElementById("NAME");

	if (typeof e == 'undefined') e = window.event;
	var theCode = e.keyCode ? e.keyCode : e.which ? e.which : e.charCode;
	if (theCode == 13)
	{
		if(MESSAGE.value == "")
		{
			alert("你忘了輸入你要說的話");		
		}
		else if(NAME.value == "")
		{
			alert("你忘了輸入名字");		
		}
		else
		{
			var MSG = MESSAGE.value;
			
			MESSAGE.value = "";
			Write(NAME.value, MSG);
		}
		return false;
	} 
	else return true;
}

function Write(NAME, MESSAGE)
{

	//LOGGER("Write() Called, MAX="+MAX+ ", NAME=" + NAME);

	try
	{

		var url="system/write.php";
		url=url+"?NAME="+encodeURIComponent(NAME);
		url=url+"&MESSAGE="+encodeURIComponent(MESSAGE);
		url=url+"&SID="+Math.random();

		WriteHTTP=GetXmlHttpObject();
		WriteHTTP.onreadystatechange=WriteCallBack
		WriteHTTP.open("GET",url,true);
		WriteHTTP.send(null);

	}
	catch(e)	
	{
		//LOGGER(e);
	}
	
}
function WriteCallBack()
{

	if (WriteHTTP.readyState==4 || WriteHTTP.readyState=="complete")
	{
		WriteRead();
	}
}

function Read()
{

	//LOGGER("Read() Called, MAX="+MAX+ ", NAME=" + NAME);
	
	try
	{
		var url="system/read.php";
		
		url=url+"?MAX="+MAX;
		url=url+"&NAME="+encodeURIComponent(NAME);
		url=url+"&SID="+Math.random();

		ReadXML=GetXmlHttpObject();
		ReadXML.onreadystatechange=ReadCallBack
		ReadXML.open("GET",url,true);
		ReadXML.send(null);

	}
	catch(e)	
	{
		//LOGGER(e);
		setTimeout('Read()', 3700);
	}

}
function ReadCallBack()
{
	if (ReadXML.readyState==4 || ReadXML.readyState=="complete")
	{
		try
		{
			var xml = ReadXML.responseXML;
					
			//LOGGER("*** OLD MAX =>"+MAX + " *** NEW MAX=>" + xml.getElementsByTagName("MAX")[0].childNodes[0].nodeValue);
			//LOGGER("*** 1 Parse MAX CHANGED? " + (MAX < parseInt(xml.getElementsByTagName("MAX")[0].childNodes[0].nodeValue)));
			//LOGGER("*** 0 Parse MAX CHANGED? " + (MAX < xml.getElementsByTagName("MAX")[0].childNodes[0].nodeValue));
			
			var newMax = parseInt(xml.getElementsByTagName("MAX")[0].childNodes[0].nodeValue);
			if(MAX < newMax)
			{
				MAX = newMax;
				
				var TIMES = xml.getElementsByTagName("TIME");
				var NAMES = xml.getElementsByTagName("NAME");
				var MESSAGES =  xml.getElementsByTagName("MESSAGE");

				var NUM_MESSAGES = NAMES.length;

				for( var i = NUM_MESSAGES-1; i >=0 ; i--)
				{
					Insert(NAMES[i].childNodes[0].nodeValue, TIMES[i].childNodes[0].nodeValue, MESSAGES[i].childNodes[0].nodeValue);
				}

			}


			var ONLINES =  xml.getElementsByTagName("ONLINE");	
			var ONLINE = document.getElementById("ONLINE");
			var NUM_ONLINES = ONLINES.length;
			ONLINE.innerHTML = "";

			var ONLINE_COUNT = document.createElement('div');
			ONLINE_COUNT.className = "ONLINE_COUNT";
			ONLINE_COUNT.innerHTML = NUM_ONLINES + " 個人在線";
			ONLINE.appendChild(ONLINE_COUNT);

			for( var i = NUM_ONLINES-1; i >=0 ; i--)
			{
			
				UpdateOnline(ONLINE, ONLINES[i].childNodes[0].nodeValue);
			}
			 setTimeout('Read()', 3700);
		}
		catch(e)
		{
			//LOGGER(e);
			setTimeout('Read()', 3700);
		}
	}
}
function WriteRead()
{

	//LOGGER("WriteRead() Called, MAX="+MAX);
	
	try
	{
		var url="system/read.php";
		
		url=url+"?MAX="+MAX;
		url=url+"&NAME="+encodeURIComponent(NAME);
		url=url+"&SID="+Math.random();

		WriteReadXML=GetXmlHttpObject();
		WriteReadXML.onreadystatechange=WriteReadCallBack
		WriteReadXML.open("GET",url,true);
		WriteReadXML.send(null);

	}
	catch(e)	
	{
		//LOGGER(e);
		setTimeout('WriteRead()', 11);
	}

}
function WriteReadCallBack()
{
	if (WriteReadXML.readyState==4 || WriteReadXML.readyState=="complete")
	{
		try
		{
			var xml = WriteReadXML.responseXML;
				
			var newMax = parseInt(xml.getElementsByTagName("MAX")[0].childNodes[0].nodeValue);
			if(MAX < newMax)
			{
				MAX = newMax;
				
				var TIMES = xml.getElementsByTagName("TIME");
				var NAMES = xml.getElementsByTagName("NAME");
				var MESSAGES =  xml.getElementsByTagName("MESSAGE");

				var NUM_MESSAGES = NAMES.length;

				for( var i = NUM_MESSAGES-1; i >=0 ; i--)
				{
					Insert(NAMES[i].childNodes[0].nodeValue, TIMES[i].childNodes[0].nodeValue, MESSAGES[i].childNodes[0].nodeValue);
				}

			}


			var ONLINES =  xml.getElementsByTagName("ONLINE");	
			var ONLINE = document.getElementById("ONLINE");
			var NUM_ONLINES = ONLINES.length;
			ONLINE.innerHTML = "";

			var ONLINE_COUNT = document.createElement('div');
			ONLINE_COUNT.className = "ONLINE_COUNT";
			ONLINE_COUNT.innerHTML = NUM_ONLINES + " 個人在線";
			ONLINE.appendChild(ONLINE_COUNT);

			for( var i = NUM_ONLINES-1; i >=0 ; i--)
			{
			
				UpdateOnline(ONLINE, ONLINES[i].childNodes[0].nodeValue);
			}
		}
		catch(e)
		{
			//LOGGER(e);
		}
	}
}

function UpdateOnline(ONLINE, NAME)
{		
	var div = document.createElement('div');
	div.innerHTML = NAME;
	div.className = "ONLINE_NAME";
	ONLINE.appendChild(div);	
}

function Insert(NAME, TIME, MESSAGE)
{
	var HISTORY = document.getElementById("HISTORY");
	var table = document.createElement('table');
	var tbody = document.createElement('tbody');
	var tr = document.createElement('tr');
	var td1 = document.createElement('td');
	var td2 = document.createElement('td');
	var td3 = document.createElement('td');
	var div1 = document.createElement('div');
	var div2 = document.createElement('div');
	var div3 = document.createElement('div');
	var textName = document.createTextNode(NAME);
	var textMessage = document.createTextNode(MESSAGE);
	var textTime = document.createTextNode(TIME);

	div1.appendChild(textTime);
	div2.appendChild(textName);
	div3.appendChild(textMessage);

	td1.appendChild(div1);
	td2.appendChild(div2);
	td3.appendChild(div3);
	td1.className = "HISTORY_TIME";
	td2.className = "HISTORY_NAME";
	td3.className = "HISTORY_MESSAGE";
	table.className = "HISTORY_ITEM";
	tr.appendChild(td1);
	tr.appendChild(td2);
	tr.appendChild(td3);
	tbody.appendChild(tr);
	table.appendChild(tbody);

	HISTORY.insertBefore(table, HISTORY.firstChild);
}

function SetName()
{
	NAME = document.getElementById("NAME").value;
}